Flush bolt



June 12, 1956 W. L. CLIFTON, JR

FLUSH BOLT 2 Sheets-Sheet 1 Filed June 19, 1953 5 an m m M1 w vO n N L f c L. M R E j T 1% L A w m /J J f .6 3 .l w. i w a \ITL T w 1% W June 12, 1956 Filed June 19. 1953 w. L. CLIFTON, JR 2,750,218

ATTORNEYS FLUSH BOLT 2 Sheets-Sheet 2 F IG.6.

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@ii 1| INVENTOR WALTER L. CLIFTON, JR.

BY M,MM 'JQQL United States Patent FLUSH BOLT Walter L. Clifton, Jr., Atlanta, Ga., assignor, by mesne assignments, to American Art Metals Company, Atlanta, Ga., a corporation of Delaware Application June 19, 1953, Serial No. 362,773

7 Claims. (Cl. 292-140) This invention relates to bolts for doors and, more particularly, to the type of bolt known as a flush bolt, and the assembly thereof in a door stile. Flush bolts are normally used in conjunction with one door of a pair of swinging or hinged doors to secure the door with respect to the head and sill of the door frame.

It is an object of the present invention to provide a new and improved flush bolt assembly which is rugged, positive in its action and substantially free from rattling.

It is another object of the present invention to provide such a flush bolt assembly in which the locking bolt is positively maintained in either an extended or retracted position and may be moved from one position to the other by turning the bolt actuating means always in the same direction.

Other objects and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the attached drawings. in which:

Fig. 1 is a partial front elevation view of the upper portion of a pair of door-s, a flush bolt assembly according to the present invention being indicated in dotted lines in one of the door-stiles;

Fig. 2 is an enlarged side elevation view, partly shortened and mostly in section, of the flush bolt assembly indicated in dotted outline in Fig. 1;

Fig. 3 is a detailed view looking in the direction of the arrows 3-3 shown in Fig. 2;

Fig. 4 is a sectional view taken on line 4-4 of Fig. 2;

Fig. 5 is a view corresponding to Fig. 4 showing a different position of the bolt actuating mechanism;

Fig. 6 is a front elevation view, partly shortened, looking toward the right of Fig. 2; and

Fig. 7 is a detailed view looking in they direction of the arrows77 shown in Fig. 5.

As has been previously mentioned, a flush bolt is normally used in conjunction with. one of a pair of hinged ice position wherein the bolt 16 is retracted so that its upper end is below the upper edge of the door. Bolt 16- is supported within the stile 14 in such a way that its upper end passes through a hole 15 in block 17 in the top of stile 14 and thence may be extended to pass into the socket 13 provided for it in the head 12 of the door frame, thereby securing the door 10. Block 17 may be of plastic or other preferably non-metallic material and serves the dual purpose of guiding bolt 16 and of preventing bolt 16 from being noisy in its operation. Guide block 17' maybe secured. to stile 14 by any suitable means but has been shown in Fig. 6 as attached to stile 14 by metal screws. 18 and 19. A good lengthv for bolt'16 has been found. to be. approximately one foot, although such length is not critical as long as the length is sufiicient to insure that the slight transverse motion. imparted to the bolt by the operating mechanism does not cause appreciable angular motion, or wobble, of the bolt 16 at is upper end. Obviously, if two flush bolt assemblies are to be used. in the same door, the length of bolt 16 must be somewhat less than half the length of the stile 14. A hole 20 has been shown in Fig. 6 for providing access to bolt 16 through stile 14.

At the end of bolt 16 which does not contact the locking socket, i. e. the lower end as shown in Fig. 2, bolt. 16 is attached by screw 20 to spindle 21 in such a way that bolt 16 has a slight degree of freedom. on spindle 21. A washer 44" is located between the head of screw 20' and bolt 16 and this Washer is preferably made of plastic material so as to deaden or minimize rattling at this pivot connection. Spindle 21 is, in turn, rigidly attached to cran-klever' 22-, shown in Fig: 3 as a circular disk, which may, if desired, be formed integrally with spindle 2'1. Crank lever 22 is itself rigidly attached to or integrally formed with spindle 23 in such a way that spindle 21, crank lever 22, and spindle 23 form a complete and rigid crank. Spindle 23 is substantially perpendicular to bolt 16 and passes through av hole shown in the stile structure at 24 and, in turn, through a hole in escutcheon plate 25, the es'cutcheon' plate being rigidly attached to stile structure 14: by metal screws 26, 27, 28, and 29, or equivalent means, as shown in Fig. 6. Spindle 23 terminates at one end in a knob or cam button 30' which is preferably formed integral with the spindle.

Cam button 30 is formed in such a way that the front surface of the cam: button as shown in Fig. 6 presents a convenient grip for the operator to use in rotating the doors. Accordingly, Fig. 1 shows a pair of hinged, or

swinging doors 10 and 11 which are in closed position beneath the head 12 ofv the doorway. One of the door stiles- 14 is shown as having an elongated substantially straight bolt or rod 16 located therein and projecting from the upper end of the stile into a recess or socket 13 located in the head 12 of the doorway. Ordinarily, the stile 14:will

include another flush bolt assembly adapted to lock the bottom. portion of the door to the door sill.

When flush bolt assemblies are installed in a door stile: as shown in Fig. 1, they are operated from the door edge when the other door is open and are thus hidden from: view when the other door is closed. While a flush bolt as-- sembly has been shown in its conventional position in Fig. 1, the assembly could be mounted in, both door stilesand be operated from the front or rear of the stile, instead of the edge, if desired. However, the usualinstallation is of the. type shown in Fig. 1 and. in the case of. metal doors, the stile which houses the flush bolt is hollow.

Fig. 2 shows thev flush bolt assembly of. Fig. 1 in a cam button. As shown in Fig. 6, the outer or front, surface of the. cam button is divided approximately into four quadrants, of which two diametrically opposed quadrants are planar. These quadrants have been designated 31 and 32. in Fig; 6. The other two diametrically opposed quadrants have been designated 33- and 34, respectively, in Fig. 6 and. are recessed. sufficiently below surfaces 31 and 32 to provide a firm. grip to the. operator as he inserts his thumb and forefinger into those recessed quadrants aud. presses against the: shoulders 43 which divide the recessed quadrants from the planar or unrecessed quadrants. In order, to operate the. cam button 30, it must be rotated in a clockwise direction. To emphasize that fact, the shoulder 43 between quadrants 32 and 33'. has been made sharp, as has the shoulder between quadrants 31 and 34. On the other hand, the shoulder between quad'rants 31 and 33 has been filleted to. give it amore gradual slope, as has the shoulder between quadrants 32 and 34. These fillets would render diflicult any attempt to rotate the cam button in a counterclockwise direction, and would remind the operator that the cam button is not meant to be rotated in that direction.

It will be noticed. by studing Figures 2 and 4 that thereare two. semi-cylindrical lugs 35. and 36. which are a part of the face of escutcheon plate: 25 and: which projectfromtheplane part. of the face of the escutcheo'n plate. These lugs 35 and 36 are made to cooperate with I cam surfaces 37 and 38 which are cut in the rear face of cam button 30. Figure 7, which is a view of the rear face of cam button 30, shows howthis face is divided approximately into four quadrants, of which two diametrically opposed quadrants are planar. These quadrants have been designated 39 and 40 in Fig. 7. The other two diametrically opposed quadrants have been designated 37 and 38, respectively, in Fig; 7, and have been machined to form cam surfaces.

respect to the planar rear surface of cam button 30 and 'each shoulder 42 may be described as having a surface extending in a plane perpendicular to the planar rear surface of the cam button. The parts of the cam surfaces next to the steep shoulders are cut to a depth equal in magnitude to the projecting length of the lugs 35 and 36 which project from the planar face of escutcheon plate 25. Hence, when steep shoulders 42 .of the cam surfaces rest against the lugs 35 and 36, respectively, the planar faces 39 and 40 of the cam button rest against the planar face of the escutcheon plate 25, as shown in Fig. 4. However, when the cam button has been rotated through slightly more than ninety degrees clockwise, Fig. shows that the cam button has ridden up on the lugs 35 and 36 until the planar surfaces 39 and 40 of the cam button are in contact with lugs 35 and 36.

Extending between the escutcheon plate 25 and the crank lever 22 is a resilient device, which may take the form of a coil spring 41 concentric with spindle 23. When cam button 30 has been rotated clockwise so that the planar surfaces 39 and 40 pass completely across the lugs 35 and 36, respectively, any further clockwise rotation of cam button 30 causes the recessed parts of the cam button to come into contact with the lugs 35 and 36, respectively. As the steep shoulders 42 of the cam button pass across the lugs, coil spring 41 causes the planar surfaces 39 and 40 to click sharply back into contact with 'escutcheon plate 25. Spring 41 causes the cam button to be held in a stable position from which it can be rotated only in a clockwise direction. The spring also holds the spindle and its associated parts against rattling.

The operation of the flush bolt assembly may be summarized as follows:

As the operator turns cam button 30 in a clockwise direction, motion is transmitted through spindle 23 to crank lever 22, which causes its spindle 21 to move circumferentially, carrying one end of bolt 16 with it. Since the other end of bolt 16 is guided to move only substantially parallel to the door stile 14, the operator thus causes the bolt 16 to be either extended or withdrawn, depending upon whether the component of motion of spindle 21 parallel to stile 14 is in a direction toward or away from the socket 13 that receives the bolt. When the bolt reaches either its completely extended position or its completely withdrawn position, the cam button clicks into a stable position so that the bolt cannot be moved by vibration or jarring. This is a very important safety feature. Rotation of the cam button 30 through an angle of 180 will either move the bolt 16 from its locked position to its unlocked position or from its unlocked position to its locked position. In either case, a click occurs at the end of the motion, and the bolt is held securely, safe from undesired disturbances. It should be noted that the cam button is turned only in a clockwise direction, whether the operator desires to lock 4 or unlock the bolt. This feature is important in simplifying the operation of the flush bolt assembly.

While I have described and illustrated an embodiment of my invention, I wish it to be understood that I do not intend to be restricted solely thereto but that I do intend to cover all modifications thereof which would be apparent to one skilled in the art and which come within the spirit and scope of my invention.

What I claim as my invention is:

l. A flush bolt assembly comprising an elongated bolt, a rotatable spindle located adjacent one end of said bolt, a crank member pivotally connecting said bolt to said spindle to cause said bolt to move longitudinally in response to rotation of said spindle, a knob located at an end of said spindle opposite said crank member, a plate member located between said knob and said crank member, said plate having an opening extending therethrough and said spindle extending through said opening, and a resilient member extending between said crank member and said plate, said resilient member engaging said crank member and urging said crank member away from said plate to cause said knob to be pressed against said plate.

2. A flush bolt assembly comprising an elongated bolt, a rotatable spindle located adjacent one end of said bolt substantially at right angles to said bolt, a crank member pivotally connecting one end of said bolt to one end of said spindle to cause said bolt to move longitudinally in response to rotation of said spindle, a knob located at the other end of said spindle, said knob having a front surface and a rear surface, a plate located between said knob and said crank member, said plate having an opening extending therethrough and said spindle extending through said opening, a spring surrounding said spindle and extending between said crank member and said plate, said spring biasing said crank member away from said plate and biasing said knob against said plate, a projection extending from said plate, and a shoulder on the rear surface of said knob engaging said projection to prevent rotation of said knob in one direction whereby said knob always has to be rotated in the other direction to operate said bolt.

3. A flush bolt assembly comprising an elongated bolt, a rotatable spindle located adjacent one end of said bolt substantially at right angles to said bolt, a crank member pivotally connecting said end of said bolt to one end of said spindle to cause said bolt to move longitudinally in response to rotation of said spindle, a rotatable knob located at the other end of said spindle, said knob having a front surface and a rear surface, and a plate located between said knob and said crank member, said plate having an opening extending therethrough and said spindle extending through said opening, said plate having a pair of lugs extending therefrom, the opening extending through said plate being located between said lugs, said rear surface of the knob having a pair of recesses therein corresponding in location to the location of said lugs, each recess being defined by a surface inclined with respect to the rear surface of the knob and a shoulder having a surface extending in a plane perpendicular to the plane of the rear' surface of the knob, said lugs being seated in said recesses, said shoulders preventing turning of said knob in one direction and said inclined surfaces permitting turning of said knob in the other direction.

4. A flush bolt assembly comprising an elongated bolt, a rotatable spindle located adjacent one end of said bolt, means pivotally connecting said bolt to said spindle to cause said bolt to move longitudinally in response to rotation of said spindle, a knob located at an end of said spindle opposite said connecting means, a member having an abutment surface located between said knob and said connecting means, said member having an opening extending therethrough and said spindle extending through said opening and a resilient member extending between said'connecting means and said abutment surface memher, said resilient member biasing said knob against said abutment surface.

5. A flush bolt assembly comprising an elongated bolt, a rotatable spindle located adjacent one end of said bolt, means pivotally connecting said bolt to said spindle to cause said bolt to move longitudinally in response to rotation of said spindle, a knob located at an end of said spindle opposite said connecting means, a member having an abutment surface located between said knob and said connecting means, said member having an opening extending therethrough and said spindle extending through said opening, said knob having a rear surface including a stop shoulder, a projection extending from said abutment surface, and a resilient member, said resilient member holding said stop shoulder in engagement with said projection to prevent turning of said knob in one direction.

6. A flush bolt assembly comprising an elongated bolt, a rotatable spindle located adjacent one end of said bolt, means pivotally connecting said bolt to said spindle to cause said bolt to move longitudinally in response to rotation of said spindle, a knob located at an end of said spindle opposite said connecting means, and a member having an abutment surface located between said knob and said connecting means, said member having an opening extending therethrough and said spindle extending through said opening, said knob having a rear surface including a recess defined by a surface inclined with respect to the rear surface of the knob and a shoulder having a surface extending in a plane perpendicular to the plane of the rear surface of the knob, said abutment surface having a projection extending therefrom into said recess, the inclined surface of said recess being positioned to ride over said projection and cam said knob away from said abutment surface when said knob is rotated in one direction.

7. A flush assembly according to claim 6 including a spring surrounding said spindle and extending between said connecting means and said abutment surface member, said spring biasing the rear surface of said knob against the projection extending from said abutment surface whereby the rear surface of said knob hits said abutment surface with an audible click when the shoulder of said recess clears said projection to permit said projection to enter said recess.

References Cited in the file of this patent UNITED STATES PATENTS 598,194 Case Feb. 1, 1898 758,333 Pfieghar Apr. 26, 1904 967,377 Henry Aug. 16, 1910 2,402,348 Schroeder June 18, 1946 FOREIGN PATENTS 110,201 Germany Mar. 3, 1899 328,391 France Jan. 9. 1903 

